The ALMA phasing system: A beamforming capability for ultra-high-resolution science at (sub)millimeter wavelengths

Artikel i vetenskaplig tidskrift, 2018

The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) has developed and deployed the hardware and software necessary to coherently sum the signals of individual ALMA antennas and record the aggregate sum in Very Long Baseline Interferometry (VLBI) Data Exchange Format. These beamforming capabilities allow the ALMA array to collectively function as the equivalent of a single large aperture and participate in global VLBI arrays. The inclusion of phased ALMA in current VLBI networks operating at (sub) millimeter wavelengths provides an order of magnitude improvement in sensitivity, as well as enhancements in u–v coverage and north–south angular resolution. The availability of a phased ALMA enables a wide range of new ultra-high angular resolution science applications, including the resolution of supermassive black holes on event horizon scales and studies of the launch and collimation of astrophysical jets. It also provides a high-sensitivity aperture that may be used for investigations such as pulsar searches at high frequencies. This paper provides an overview of the ALMA Phasing System design, implementation, and performance characteristics.

Methods: observational

Instrumentation: interferometers

Instrumentation: high angular resolution

Författare

L. D. Matthews

Massachusetts Institute of Technology (MIT)

G. Crew

Massachusetts Institute of Technology (MIT)

S. Doeleman

Harvard-Smithsonian Center for Astrophysics

Massachusetts Institute of Technology (MIT)

R. Lacasse

National Radio Astronomy Observatory

A. F. Saez

Atacama Large Millimeter-submillimeter Array (ALMA)

W. Alef

Max Planck-institutet

K. Akiyama

Massachusetts Institute of Technology (MIT)

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

R. Amestica

National Radio Astronomy Observatory

J. M. Anderson

Max Planck-institutet

Deutsches GeoForschungsZentrum (GFZ)

D. A. Barkats

Atacama Large Millimeter-submillimeter Array (ALMA)

Harvard-Smithsonian Center for Astrophysics

A. Baudry

Universite de Bordeaux

D. Broguière

Institut de RadioAstronomie Millimetrique (IRAM)

R. Escoffier

National Radio Astronomy Observatory

V. Fish

Massachusetts Institute of Technology (MIT)

J. Greenberg

National Radio Astronomy Observatory

M. H. Hecht

Massachusetts Institute of Technology (MIT)

R. Hiriart

National Radio Astronomy Observatory Socorro

A. Hirota

Atacama Large Millimeter-submillimeter Array (ALMA)

M. Honma

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

The Graduate University for Advanced Studies (SOKENDAI)

P. T.P. Ho

Academia Sinica

C. M. V. Impellizzeri

Atacama Large Millimeter-submillimeter Array (ALMA)

M. Inoue

Academia Sinica

Y. Kohno

National Institutes of Natural Sciences - National Astronomical Observatory of Japan